Exceptional Survival in Danish and Italian Families We propose research requested in the NIA RFA on "Exceptional Survival in Families" (ESF). In particular, we plan to gather questionnaire and physiological data on 1000 pairs (half in Denmark and half in Italy) of living nonagenarian and centenariala sibs and their living brothers, sisters and children. We will also gather information on the lifespans of the sibs' parents. We will validate ages by examining birth certificates and, when appropriate, marriage certificates and death certificates. We will collaborate with other ESF Study Centers to develop appropriate questionnaires and survey procedures. We will develop powerful, appropriate models and methods of statistical/demographic analysis to study the data in collaboration with other ESF Study Centers.